When the Dial Tone Dies: Getting Your Support Number Ready for the UK's PSTN Switch-Off

By the end of January 2027, the UK's old analogue phone network will be switched off. That is not a drill or a consultation. The Public Switched Telephone Network — the system that has carried landline calls for generations — is being retired, along with ISDN lines that many small firms still use for calls, card machines and alarms. As of November 2026, we are in the final stretch. If your customer support number still runs over a traditional phone line, now is the moment to check what is plugged into it.

What is actually happening?

Openreach, which runs most of the UK's phone network, has already stopped selling new analogue lines. The full withdrawal is scheduled for 31 January 2027. After that, old-style phone lines will no longer work. Calls will move to digital services that run over broadband — often called VoIP or digital voice — or to mobile. For many households and businesses, this will be invisible. For a small business with a support line, a fax machine, a lift phone or an intruder alarm on the same line, it is a practical project, not a tap on the app.

Why support numbers need special attention

A support number is not just a number. It is the front door for customers who have a problem. If it goes down, they do not wait politely — they ring a competitor. Digital phone services usually run through a router. That means the phone depends on power and a working internet connection. A power cut or broadband outage can silence the line unless you have a battery backup, a mobile fallback or a second connection. That is not a reason to panic. It is a reason to plan.

A practical checklist for the next few months

1. Audit every device that rides on the old line

Walk around the premises with a notepad. List every extension, fax machine, PDQ card terminal, alarm panel, lift line, door entry system, CCTV box and EPOS till that uses a phone line. Do not forget the line that only rings in the stockroom. Ask your alarm company and card terminal provider whether their kit is compatible with digital lines. Some legacy devices need an adapter; others need replacing.

2. Choose between hosted VoIP and a managed service

Hosted VoIP is the simple route for most small support teams. You buy seats from a provider, use handsets or a softphone, and manage call routing in a web portal. It is flexible and has low upfront cost. A managed service costs more but can include a service-level agreement, on-site support and kit that keeps working when the broadband wobbles. If you run a multi-site operation or a busy contact centre, the managed route is worth pricing. If you are a five-person firm answering calls from a desk, hosted is usually enough.

3. Keep your existing number

You do not have to lose the number customers know. Number porting lets you move an existing number to a new provider. The key rule: do not cancel your old line before the port completes. Ask the new provider to handle the port and give you a date in writing. Lead times can stretch when lots of businesses move at once, which is another reason not to leave it until January.

4. Test call quality like you mean it

Digital calls are only as good as the broadband underneath. Run a speed test, but also check for jitter and packet loss. Use a wired handset for the main support desk rather than Wi-Fi. Ask your provider about quality-of-service settings that prioritise voice traffic. Make a few test calls at your busiest time of day. If the line sounds garbled or drops, fix it before the old line disappears.

5. Add a resilience layer

A digital phone that dies when the power goes is a business risk. Ask for a battery backup for the router and the fibre box. Keep a charged mobile with a signal in the building. Set up call forwarding to a mobile if the broadband fails. For a support line, a simple fallback can be the difference between a quiet hour and a lost customer.

6. Update your details and train the team

Change the number on your website, Google Business Profile, invoices, email signatures and van livery if needed. Show staff how to transfer calls, park calls and check voicemail on the new system. A short training session beats a week of confused customers.

The risk of waiting for the final months

The switch-off is not a surprise, but many businesses will treat it like one. The final months are when porting queues grow, engineers get booked up and hardware goes out of stock. Alarm and lift engineers may need lead time to visit. If you leave it until December 2026 or January 2027, you are competing for attention with every other firm that did the same. A planned move in late 2026 is cheaper and calmer than an emergency migration in 2027.

The EasyToCall take

You do not need to understand the engineering to get this right. You need a list of what is plugged in, a provider who explains the options in plain English and a test call before the old line goes quiet. The landline is retiring. Your support number does not have to retire with it.